Shrien Dewani 'sent texts plotting wife's murder as he sat next to her in taxi on safari trip'

Murder suspect Shrien Dewani allegedly sent texts plotting to kill his wife - while she was sitting next to him looking at honeymoon photos.

Zola Tongo, a taxi driver who has confessed to the murder of Anni Dewani, 28, claims that Mr Dewani was haggling over payment for the killing in the back of his taxi while returning from a safari trip.

Tongo's allegations will be aired tonight in a Dispatches documentary on Channel 4 about the murder of Mrs Dewani on her honeymoon in South Africa last year.

Wedding day: Anni Dewani was murdered on her honeymoon in November

The taxi driver implicated Mr Dewani in the murder in order to secure a reduction in his own punishment. He was sentenced to 18 years in prison in December.

Tonight's documentary will also cover the concerns of Mrs Dewani's family that the marriage was in trouble from the outset.

Shrien Dewani has been accused of arranging his wife's murder via text message

Mr Dewani, 31, a care home manager from Bristol, is being held at a secure mental health unit. His lawyers are returning to court on Monday as he fights extradition to South Africa.

Xolile Mngeni and Mziwamadoda Qwabe are accused of being the gunmen who shot Swedish-born Mrs Dewani in the back of a taxi in Guguletu township, near Cape Town on November 13 last year. Tongo’s solicitor, William Da Grass, tells Dispatches his client claims he and Mr Dewani exchanged text messages discussing payment for the killing while in the same car as the victim.

Mr Da Grass said his client claims that: 'She was looking at a digital camera at the time. They had been at a game park and she was looking at photos regarding their travels on their honeymoon whilst these negotiations were being carried on in her presence.'

Reports show Mrs Dewani was not sexually assaulted or raped. She was shot through the hand and neck, possibly as she lay face down in the taxi.

A male prostitute calling himself the 'German Master', who claimed to the Sun that he had sexual liaisons with Mr Dewani, also features in the programme. Mr Dewani has dismissed claims that he was secretly homosexual as 'ludicrous'.

Convicted: Taxi driver Zola Tongo has implicated Mr Dewani as part of his plea bargain

The Dewanis are confident that the claims of the German Master are easily demolished and that so far all the allegations made by South African police are circumstantial. The defence insist Mrs Dewani was the victim of a carjacking, arranged by Tongo, and that she may have been accidentally shot by one of the carjackers as he tried to rape her.

Mrs Dewani's sister Ami Denborg tells Dispatches that the British businessman’s refusal to have sex with his bride-to-be caused some concern.

Tensions: Despite their apparent harmony, Mrs Dewani's family saw cracks in her relationship with her husband

Ms Denborg said: 'Personally I think it was quite strange if the guy says that he doesn’t want to have sex before marriage. On the other hand in our culture it’s very respectful if you don’t want to and Anni accepted that and so did we.

'A couple of weeks before the wedding she threw her ring back at Shrien and explained that she didn’t want to get married.

'She called me and talked to me about it and I thought, "OK, are you sure you’re not just stressed out because of all the arrangements," and it ended up her realising maybe it was stress and after a couple of days she went back to him.'

Sources close to Mr Dewani said the couple always resolved their disagreements.

None of Mr Dewani's lawyers were immediately available for comment.

Vinod Hindocha, Mrs Dewani's father, had to console her on her wedding day